Method for assisting normal breathing in a mammal having a lung disorder

Abstract

A method of assisting a mammal having a lung disorder to breathe ambient gas normally, i.e., without the assistance of a ventilator. The method includes providing an animal having a lung disorder, such as surfactant deficiency, stiff lung or hyperinflated lung syndrome, and instilling a perfluorochemical liquid into the trachea for administration in the alveolar sacs of a lung of the animal. The perfluorochemical is permeable to the ambient gas and resides substantially permanently within the alveolar sacs without inducing hyperinflated lung syndrome. The liquid is instilled in an amount sufficient to enable the animal to breathe the ambient gas normally with O 2 /CO 2 blood gas exchange. In another aspect of the invention, the method further includes the step of alleviating the lung disorder without inducing hyperinflated lung syndrome.

What is claimed is: 
     
       1. A method of assisting a mammal having a lung disorder to breathe ambient gas normally comprising: providing an animal having a lung disorder;   instilling a perfluorochemical liquid into the trachea for administration in the alveolar sacs of said animal, said perfluorochemical liquid being permeable to ambient gas and residing substantially permanently within said alveolar sacs without inducing hyperinflated lung syndrome, said perfluorochemical liquid in an amount sufficient to enable said animal to breathe said ambient gas normally with O 2  /CO 2  blood gas discharge; and   removing any breathing-assisting devices to allow said animal to breathe ambient gases normally and without mechanical assistance.   
     
     
       2. The method of claim 1 further comprising the step of alleviating said lung disorder without inducing hyperinflated lung syndrome. 
     
     
       3. The method of claim 1 wherein said ambient gas is atmospheric air. 
     
     
       4. The method of claim 1 wherein said perfluorochemical has a boiling point of at least about 145° C. at atmospheric conditions. 
     
     
       5. The method of claim 1 wherein said perfluorochemical has a boiling point of at least about 150° C. at atmospheric conditions. 
     
     
       6. The method of claim 1 wherein said perfluorochemical is selected from the group consisting of perfluorophenanthrene, perfluoromethyldecalin, perfluorodimethylethylcyclohexane, perfluorodimethyldecalin, perfluorodiethyldecalin, perfluoromethyladamantane, perfluorodimethyladamantane, perfluoroisopropylbromopentylether, perfluoroisopropylbromohexylether, perfluoroisopropylbromoheptylether, perfluoroisopropylbromooctylether, perfluoroisopropylbromononylether, perfluoroisopropylbromodecylether, and mixtures thereof. 
     
     
       7. The method of claim 1 wherein said perfluorochemical is in the form of a neat liquid or an aqueous emulsion. 
     
     
       8. The method of claim 1 wherein said perfluorochemical is instilled at a dose of about 0.1 ml/kg to about 15 ml/kg of bodyweight. 
     
     
       9. The method of claim 1 wherein said perfluorochemical is instilled at a dose of about 1 ml/kg to about 6 ml/kg of bodyweight. 
     
     
       10. The method of claim 1 wherein said lung disorder is a surfactant deficiency. 
     
     
       11. The method of claim 1 wherein said lung disorder is hyperinflated lung syndrome. 
     
     
       12. A method of assisting a mammal having a deficiency of lung surfactant to breathe ambient atmospheric gas normally without mechanical assistance, the method comprising the steps of: providing an animal having a deficiency of lung surfactant;   supporting the breathing of said animal mechanically while the following step of the method is carried out;   instilling perfluorophenanthrene, in an amount ranging from about 1 to 6 ml/kg, into the trachea for administration in the alveolar sacs of said animal, said perfluorophenanthrene being an amount sufficient to enable said animal to breathe said ambient gas normally with O 2  /CO 2  blood gas discharge residing substantially permanently within said alveolar sacs without inducing hyperinflated lung syndrome; and   removing any breathing-assisting devices to allow said animal to breathe ambient atmospheric gases normally without mechanical assistance.   
     
     
       13. A method for ensuring normal substantially normal respiration of a mammal and ameliorating hyperinflated lung damage from administration of a perfluorocarbon-based blood substitute comprising the steps of: administering intravascularly a perfluorocarbon-based blood substitute containing an emulsion of a first perfluorocarbon; and   administering intratracheally an effective dose of a second perfluorocarbon, perfluorophenanthrene, to reside in the lungs of said animal at least until substantially all of the first fluorocarbon has dissipated from the mammal.